Abstract Child victimization jeopardizes the healthy development of millions of American children every day. Minority, low income, and rural children are disproportionately exposed to more frequent, severe, and diverse forms of victimization (i.e., peer bullying, assault, physical and sexual abuse, property crime, neglect, and psychological maltreatment). Child victimization by peers is linked to psychosis by late childhood/adolescence1-4 and harms educational outcomes due to higher absenteeism, reduced growth in reading and math, less engagement in positive youth development activities, higher rates of school drop-out, and greater risk for substance abuse, delinquency, and violent adolescent behavior.5-8 The radKIDS Personal Empowerment and Safety Education Program is a community-based program developed in response to national guidelines for educating children in child safety and preventing victimization. radKIDS uses activity-based skill training to help children develop personal safety boundaries, critical thinking skills for responding to threats of danger, age-appropriate coping strategies for dealing with current and past victimization, self-assertiveness and physical skills for self-defense, communication skills for reporting incidences to parents/adults, and growing child self- worth?the program's cornerstone for personal safety and healthy development. The proposed project will adapt the radKIDS instructor training into a technology-based delivery system that can be used for broad-scale dissemination in schools. The long-term goal of radKIDS 2.0 is to provide a scalable training solution for all radKIDS curriculum that meets school mandates for bullying and victimization prevention, is aligned with national guidelines for effective child safety education, and is easily implemented with fidelity. In Aim 1, we use an 8 member expert advisory panel to help guide the adaptation of the current radKIDS instructor training into a multimedia, blended learning approach to support scale, dissemination, and implementation that maintains treatment fidelity. This system will include an interactive multimedia web and mobile application that includes an online pre-service training; a streamlined 1-day in-person training on program values, behavioral skill training, and physical skill competencies; video demonstrations of individual and group physical self-defense skills and activity practice drills; instructor-in-training guidance, featuring expert trainer review of instructor capture and upload of video by web browser or mobile app to maximize fidelity: revised and standardized child instructional content on the program's introduction to personal child safety and boundaries, and risk reduction approaches for school safety; an instructor's guide including syllabi, detailed scripts for instructor-student guided question-answer interactions; diagramed setups for simulated escape plan drills; materials for student homework and practice; and program information for parents. In Aim 2, we will evaluate the usability and feasibility of the RadKids 2.0 with 20 pairs of program instructors (n=40) from diverse backgrounds and geographical locations nationally to evaluate the radKIDS 2.0 training program and child instructional modules. If Phase I is successful, our plans for Phase II are to: (a) complete remaining instructor training for the program; (b) modify the remaining 6 child curriculum modules, and (c) evaluate the completed program using a randomized trial.